Why Trump will be allowed to win the nomination
Two simple reasons, IMO.
First, the anti-Trump movement within the party has clearly failed. Coming up with some convention rule or whatever will cause significant conflict within the party. They don't want to throw all those votes away for the long-term.
Not messing with the voting equipment this election would help them make it seem like the whole voting system isn't totally jacked up.
This serves two goals of the Rethug party. Trump doesn't win and nobody can argue with the voting stats. It's a win-win for them if you think about it. I can't discuss the current primary in here but will a Democrat automatically hold on for a second term? I'm not so sure and even if the answer is yes, to them, eight years of a Democratic president is likely still better than the fracturing of the whole Rethug party.
I think the Thugs will cut their losses, let Trump win the nomination and then not tamper with the actual votes. In the long term, it's the better strategy. Heck, it probably is the better strategy in the short or medium term.
And yes, I do realize how paranoid this post sounds. Sigh. Wonder how I got there.